Colonel Mamadou Moustapha Ndala, who led Congolese army soldiers on the front lines during their victory against the M23 rebels, was killed on Thursday in Beni, North Kivu province, during an ambush.

According to military sources, Col. Mamadou Ndala died after a rocket hit his vehicle near the village of Mazizi.

Government spokesman Lambert Mende called his death “an immense loss for the armed forces and the republic.” He blamed Ugandan ADF-Nalu rebels for the attack.

Considered a hero in DR Congo for leading Congolese troops on the front lines during their victory against the M23 rebels, Col. Mamadou Ndala had been leading the new army operations against the ADF-Nalu rebels in the Beni region.

Many Congolese expressed shock and deep sadness on Thursday after learning of his death. Messages posted on social media sites expressed gratitude for a man who fought and gave his life for his country.

Some questioned the official version given by the Congolese authorities blaming his death on an attack by ADF-Nalu rebels. They demanded a throughout investigation on the circumstances of his death.

Col. Mamadou Ndala was a very popular commander with his troops but also the population he was fighting to protect. In July of last year, after rumors spread that he was about to be replaced as the commander of a Special Forces unit protecting the city of Goma, massive protests erupted in the city demanding that he be kept at his post.

In November, he was on the forefront as the Congolese Armed Forces (FARDC) dislodged the M23 rebels from all the territories they had occupied in North Kivu province for more than a year.